Polymerization of olefins

Abstract

Olefins are polymerized by novel transition metal complexes of selected iminocarboxylate and iminoamido ligands, sometimes in the presence of cocatalysts such as alkylaluminum compounds or neutral Lewis acids. Olefins which may be (co)polymerized include ethylene, alpha-olefins, and olefins containing polar groups such as olefinic esters for example acrylate esters. Also described are certain "Zwitterionic" transition metal complexes as polymerization catalysts for making polar copolymers. The resulting polymers are useful as thermoplastics and elastomers.

What is claimed is:  
     
       1. A process for the polymerization of olefins, comprising the step of contacting, under olefin polymerizing conditions, a monomer component comprising one or more of an olefin of the formula H 2 C═CHR 4 , a norbornene, a styrene, a cyclopentene or a polar olefin, with a transition metal complex of a ligand of the formula                    
       wherein: 
       Y is oxo, NR 12  or PR 12    
       Z is O, NR 13 , S or PR 13 ;  
       each of R 1 , R 2  and R 3  is independently hydrogen, hydrocarbyl, substituted hydrocarbyl or a functional group;  
       n is 0 or 1;  
       R 4  is hydrogen, alkyl or substituted alkyl;  
       R 5  is a covalent bond, alkylene or substituted alkylene;  
       R 6  is hydrogen, a metal cation, hydrocarbyl or substituted hydrocarbyl;  
       each R 12  is independently hydrogen, hydrocarbyl, substituted hydrocarbyl or a functional group;  
       each R 13  is independently hydrogen, hydrocarbyl, substituted hydrocarbyl or a functional group;  
       and provided that:  
       any two of R 1 , R 2  and R 3  geminal or vicinal to one another taken together may optionally form a ring, and  
       when Z is O and Y is NR 12 , n is 1.  
     
     
       2. The process of  claim 1 , wherein the transition metal is a Group 3-11 transition metal. 
     
     
       3. The process of  claim 2 , wherein the transition metal is selected from the group consisting of Ni, Zr, Ti, Fe, Co and Cu. 
     
     
       4. The process of  claim 1 , wherein Z is O or NR 13  and n is 0. 
     
     
       5. The process of  claim 1 , wherein: 
       Y is oxo, Z is NR 13 , R 1  is hydrogen or hydrocarbyl, n is 0, and R 13  is hydrocarbyl or substituted hydrocarbyl having an E s  of less than −1.0 or aryl or substituted aryl in which at least one bond vicinal to the free bond of the aromatic group is substituted; or  
       Y is NR 12  and Z is NR 13 , n is 0, R 1  is hydrogen or hydrocarbyl, R 12  and R 13  are each independently hydrocarbyl or substituted hydrocarbyl, one or both of which has an E s  of less than −1.0, or aryl or substituted aryl in which at least one bond vicinal to the free bond of the aromatic group is substituted.  
     
     
       6. The process of  claim 1 , wherein the transition metal complex has the formula (L 1 ) x (L 2 ) y (L 3 ) z M (VIII), wherein L 3  is (I); z is 1 or 2; M is a transition metal of oxidation state q; y is an integer of 1 to 3; x=(q−z); each L 1  is independently a monodentate, monoanionic ligand, wherein at least one L 1  group is a ligand that adds to an olefin; and L 2  is a monodentate neutral ligand which is displaced by an olefin, or an empty coordination site; or L 1  and L 2  taken together are a monoanionic, bidentate ligand into which an olefin molecule inserts between the ligand and M. 
     
     
       7. The process of  claim 1 , wherein the transition metal complex has the formula                    
       wherein M is the transition metal; each L 1  is independently a monodentate, monoanionic ligand, wherein at least one L 1  group is a ligand that adds to an olefin; and L 2  is a monodentate neutral ligand which is displaced by an olefin, or an empty coordination site; or L 1  and L 2  taken together are a monoanionic, bidentate ligand into which an olefin molecule inserts between the ligand and M. 
     
     
       8. The process of  claim 1 , wherein a cocatalyst is present. 
     
     
       9. The process of  claim 1 , wherein the monomer component comprises ethylene.